Cod sursa(job #2123476)

Utilizator radiogard1999Dragoi Andrei radiogard1999 Data 6 februarie 2018 12:02:10
Problema Arbori indexati binar Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.24 kb
#include <bits/stdc++.h>
#define Nmax 100005
using namespace std;
ifstream fin ("aib.in");
ofstream fout ("aib.out");
int aib[Nmax], n, Q;
inline void Update(int poz,int val)
{
    while(poz<=n)
    {
        aib[poz]+=val;
        poz+=(poz&(-poz));
    }
}
inline int Sum(int poz)
{
    int sum=0;
    while(poz>=1)
    {
        sum+=aib[poz];
        poz-=(poz&(-poz));
    }
    return sum;
}
inline int Binary_Search(int x)
{
    int st=1,dr=n,mij,poz=-1;
    while(st<=dr)
    {
        mij=(st+dr)/2;
        if(Sum(mij)==x)
        {
            poz=mij;
            dr=mij-1;
        }
        else if(Sum(mij)>x)
            dr=mij-1;
        else st=mij+1;
    }
    return poz;
}
int main()
{
    int x,op,y;
    fin>>n>>Q;
    for(int i=1;i<=n;i++)
    {
        fin>>x;
        Update(i,x);
    }
    while(Q--)
    {
        fin>>op;
        if(op==0)
        {
            fin>>x>>y;
            Update(x,y);
        }
        else if(op==1)
        {
            fin>>x>>y;
            fout<<Sum(y)-Sum(x-1)<<"\n";
        }
        else
        {
            fin>>x;
            fout<<Binary_Search(x)<<"\n";
        }
    }
    fin.close();
    fout.close();
    return 0;
}